What is the best way to allow a user to use multiple email addresses in Exchange?

I have a number of users from another company merging with ours. I am migration them onto my Server 2003 Standard, Exchange Enterprise system but need to give them the ability to easily go back and forth between their old email address (old company) and their new one (merged company). Is there anyway to accomplish this other than two seperate AD accounts with two seperate Inboxes in Outlook?

Everything I have read would make it seem that I need to create different AD objects for each of them and then use their Outlook to connect one exchange account and one Imap account. Is that correctand is there a cleaner way to do it?

I haven't pulled it over to my server yet but what i am looking for is to give them the ability to easily determine which address mail they are sending is coming from. They wouldn't have the ability to change it within the recipient policy.

The drop-down you get with multiple accounts is ideal but you end up with multiple inboxes and confused users.

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The way my users are setup here are @companyname.com is their primary SMTP address, then we have all the @legacydomains as alternative SMTP addresses, that way mail to user@legacydomain.com still reaches them, but the new email out is always as @user@companyname.com

On the other side, if the users are only going to be sending out as their @legacydomain.com email, just set that as their primary SMTP address.

A couple of months ago we ran into an issue that necessitated re-creating our Edge Subscriptions. However, when we attempted to execute the command: New-EdgeSubscription -filename C:\NewEdgeSub_01.xml we received an error indicating that the LDAP se…

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